Light emitting device

ABSTRACT

A light emitting device includes a substrate, a light emitting element, and a light reflecting member. The substrate includes a base material having a rectangular planar shape, a connection terminal disposed on a first main surface of the base material, and an outer connection portion disposed on a second main surface of the base material opposite to the first main surface. The connection terminal includes a protruding portion, and the connection terminal is connected to the outer connection portion via a through hole defined in the base material. The light emitting element is connected to the connection terminal on the first main surface of the base material via a molten bonding material. The light reflecting member covers the light emitting element.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. patentapplication Ser. No. 15/584,150 filed on May 2, 2017. This applicationis a continuation application of U.S. patent application Ser. No.14/333,850, filed on Jul. 17, 2014, now U.S. Pat. No. 9,673,364. Thisapplication claims priority to Japanese Patent Applications No.2013-150445 filed on Jul. 19, 2013, No. 2013-150462, filed on Jul. 19,2013 and No. 2014-104074 filed on May 20, 2014. The entire disclosuresof U.S. patent application Ser. Nos. 15/584,150 and 14/333,850, andJapanese Patent Application Nos. 2013-150445, 2013-150462, and2014-104074 are hereby incorporated herein by reference.

BACKGROUND Technical Field

The present disclosure relates to a light emitting device, and to amethod of manufacturing the same.

Related Art

In the prior art, a light emitting device has been proposed that isconfigured as a chip scale package (CSP) having similar size as a lightemitting chip (for, example, JP2001-223391A). This type of lightemitting device is suitable for a top-view mounting method, and as thelight emitting device itself is thin, the light emitting device can beused extremely efficiently depending on its use. Furthermore, the lightemitting device enables enhanced production efficiency and realizesfurther reduction in thickness by formation of a projecting portion on alead electrode that is provided in the package.

On the other hand, a side-view type light emitting device is used as abacklight light source for a display panel of an electronic device orthe like.

For example, a side-view type light emitting device is proposed whichincludes a chip-shaped base material having a recessed portion, a lightemitting element, and a substrate which is formed on the surface of thebase material and have a pair of terminals connected with the lightemitting element (for example, JP H08-264842A). The light emittingdevice is configured so that the pair of terminals that extend frombelow the light emitting element, are disposed in the periphery of thesurface in proximity to both end surfaces of the base material.

SUMMARY

The present disclosure relates to a light emitting device. A lightemitting device includes a substrate, a light emitting element, and alight reflecting member. The substrate includes a base material having arectangular planar shape, a connection terminal disposed on a first mainsurface of the base material, and an outer connection portion disposedon a second main surface of the base material opposite to the first mainsurface. The connection terminal includes a protruding portion, and theconnection terminal is connected to the outer connection portion via athrough hole defined in the base material. The light emitting element isconnected to the connection terminal on the first main surface of thebase material via a molten bonding material. The light reflecting membercovers the light emitting element.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic perspective view illustrating a light emittingdevice according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along line A-A′ of the lightemitting device of FIG. 1.

FIG. 3 is a perspective plan view of the light emitting device of FIG.1.

FIG. 4 is a schematic perspective view illustrating the light emittingdevice of FIG. 1 which is mounted on a mounting board.

FIG. 5A is a schematic perspective plan view illustrating a method ofthe light emitting device of FIG. 1.

FIG. 5B is across-sectional view taken along line B-B′ of FIG. 5A.

FIG. 6 is a schematic cross-sectional view illustrating a light emittingdevice according to another embodiment of the present invention.

FIG. 7 is a schematic cross-sectional view illustrating a light emittingdevice according to still another embodiment of the present invention.

FIG. 8A is a schematic plan view illustrating a light emitting deviceaccording to still another embodiment of the present invention.

FIG. 8B is a side view viewed from a side of arrow E of FIG. 8A.

FIG. 8C is a cross-sectional view taken along line F-F′ of FIG. 8A.

FIG. 8D is a cross-sectional view taken along line G-G′ of FIG. 8A.

FIG. 8E is a plan view of a substrate in the light emitting device ofFIG. 8A.

FIG. 8F is a perspective view of the substrate viewed from a side ofarrow E of FIG. 8E.

FIG. 8G is a perspective back side view of the substrate of FIG. 8E.

FIG. 9A is a schematic plan view illustrating a light emitting deviceaccording to still another embodiment of the present invention.

FIG. 9B is a side view viewed from a side of arrow E of FIG. 9A.

FIG. 9C is a cross-sectional view taken along line F-F′ of FIG. 9A.

FIG. 9D is a cross-sectional view taken along line G-G′ of FIG. 9A.

FIG. 9E is a plan view of a substrate in the light emitting device ofFIG. 9A.

FIG. 10 is a schematic plan view illustrating a shape of a protrudingportion of a connection terminal in the light emitting device accordingto still another embodiment of the present invention.

FIG. 11 is a schematic cross-sectional view illustrating a lightemitting device according to still another embodiment of the presentinvention.

FIG. 12A is a partial schematic perspective plan view illustrating alight emitting device according to still another embodiment of thepresent invention.

FIG. 12B is a side view of FIG. 12A.

FIG. 12C is a cross-sectional view of FIG. 12A.

FIG. 12D is a plan view if the substrate in the light emitting of FIG.12A.

FIG. 12E is a cross-sectional view if the substrate in the lightemitting of FIG. 12A.

FIG. 12F is a back side view if the substrate in the light emitting ofFIG. 12A.

FIG. 12G is a schematic plan view of the substrate illustrating a methodof the light emitting device of FIG. 12A.

FIG. 13A is a partial schematic perspective plan view illustrating alight emitting device according to still another embodiment of thepresent invention.

FIG. 13B is a side view of FIG. 13A.

FIG. 13C is a cross-sectional view of FIG. 13A.

FIG. 13D is a plan view if the substrate in the light emitting of FIG.13A.

FIG. 13E is a cross-sectional view if the substrate in the lightemitting of FIG. 13A.

FIG. 13F is a back side view if the substrate in the light emitting ofFIG. 13A.

FIG. 13G is a schematic plan view of the substrate illustrating a methodof the light emitting device of FIG. 13A.

FIG. 14 is a schematic perspective view illustrating a light emittingdevice according to an embodiment of the present invention.

FIG. 15 is a cross-sectional view taken along line A-A′ of the lightemitting device of FIG. 14.

FIG. 16 is a perspective plan view of the light emitting device of FIG.14.

FIG. 17 is a schematic perspective view illustrating the light emittingdevice of FIG. 14 which is mounted on a mounting board.

FIG. 18A is a schematic plan view illustrating a method of the lightemitting device of FIG. 14.

FIG. 18B is a cross-sectional view taken along line B-B′ of FIG. 18A.

FIG. 19A is a plan view illustrating a light emitting device accordingto another embodiment of the present invention.

FIG. 19B is a cross-sectional view taken along line C-C′ of the lightemitting device of FIG. 19A.

FIG. 20 is a plan view illustrating a light emitting device according toanother embodiment of the present invention.

DETAILED DESCRIPTION

As the mounting method of the side-view type light emitting devicediffers from that of the top-view type disclosed above, it is difficultfor the side-view type light emitting device to achieve the stability ofthe mounting, the light flux distribution, or the like at a similaramount to the top-view type light emitting element.

In particular, due to the need for further downsizing and reductions inthickness in light emitting devices in recent years, the substrate isbecoming flatter and is scaling down to minimize the occupied space ofthe chip scale package itself. Consequently, there has been a transitionin a metal member used as a terminal from a tabular lead electrode to ametallic film formed directly on the substrate itself as a thinelectrode film. Even in the case where this type of metallic film isused in the package, and in particular in relation to a side-view typelight emitting device, there is a need for a light emitting element thatenables stable and highly accurate arrangement and mounting withoutelement failure during the arrangement of the light emitting elementonto the package and the mounting onto the mounting board of the lightemitting device. Furthermore, a light emitting device, that emits lightfrom a side surface and is mounted on a mounting board to orient thelight extraction surface in a lateral direction, is mounted on a solderor the like disposed on the same surface as the terminal on which thelight emitting element is mounted.

Even when for example the light emitting element is sealed with asealing member, a portion of the solder or the like that is disposed onthe same surface, or the flux contained in the solder of the like alongthe end surface penetrates between the sealing member and the terminal,and thus the reliability of the light emitting device may be degraded.

In particular, in a light emitting device that meets a need for areduction in width, since the terminal on which the light emittingelement is mounted and the terminal that is fixed with the solder or thelike are disposed closely, the allowable margin for penetration ofsolder or the like is extremely small, and the defects described abovemay occur.

Consequently, there is a need to realize further enhanced lightextraction efficiency of the light emitting element as there is the needfor further high output, high illumination, and the like by smallerlight emitting chips.

The present disclosure is proposed in relation to the problems above,and has the object of providing a small and thin light emitting devicethat enables a stable and highly accurate arrangement and mountingwithout element failure during the arrangement of the light emittingelement onto the package and the mounting onto the mounting board of thelight emitting device.

According to the present disclosure, even the light emitting device is asmall and thin, a stable and highly accurate arrangement and mountingcan be carried out without element failure during the arrangement of thelight emitting element onto the package, and the mounting onto themounting board of the light emitting device.

Embodiments for implementing the light emitting device and the method ofmanufacturing the light emitting device of the present invention will bedescribed below with reference to the accompanying drawings. In thefollowing embodiment of the light emitting device and the method ofmanufacturing the light emitting device that embody the technologicalconcept of the present invention are just examples, and unless otherwisespecified, the constituent parts discussed in the embodiments are notintended to limit the scope of the present invention. Further,constitutions described in examples and the embodiments can be employedin other examples and embodiments. The sizes and the arrangementrelationships of the members in each of drawings are occasionally shownexaggerated for ease of explanation.

In one embodiment, the light emitting device includes a substrateprovided with a pair of connection terminals, a light emitting element,and a light reflecting member. This light emitting device may be used inany appropriate mounting manner, however it is preferred that the lightemitting device is mounted in a mounting configuration termed aside-view type, a so-called side surface light emitting type. That is tosay, the mounting surface is configured as a surface that is adjacent tothe light extraction surface.

Also, in another embodiment, the light emitting device includes asubstrate provided with a pair of connection terminals, a light emittingelement, a sealing member and an insulating member.

In this specification, the light extraction surface of the lightemitting device may be termed the upper surface, the surface that isclosely adjacent to or intersects with the light extraction surface maybe termed the side surface, and one of the side surfaces may be termedthe mounting surface for the light emitting device. In this manner, thesurface that corresponds to the light extraction surface of the lightemitting device of the surfaces of the respective members and therespective elements that configure the light emitting device may betermed a first main surface (that is to say, the upper surface), and thesurface that is opposite to the first main surface may be termed asecond main surface (that is to say, the lower surface). The surfacethat is closely adjacent to or intersects with to the first main surfaceand the second main surface (that is to say, the surface thatcorresponds to the side surface of the light emitting device) may betermed the end surface.

Substrate

The substrate includes a pair of connection terminals corresponding tonegative and positive electrode at least on the first main surfacethereof. These connection terminals normally are formed at least on thefirst main surface of the base material. The first main surface isdenoted as the surface of one of the substrate or the base material.

There is no limitation in relation to the shape of the substrate,however, the shape of the substrate may correspond to the shape of thebase material as described below. For example, at least the first mainsurface is preferably elongated in a longitudinal direction, and morepreferably includes a short dimension that is orthogonal to thelongitudinal direction.

Base Material

The base material may be formed by any appropriate material, and forexample, includes a metal, ceramic, resin, dielectrics, pulp, glass,paper or a composite material of those materials, or a compositematerial of those materials and a conductive material (for example, ametal, carbon, or the like). The metal includes copper, iron, nickel,chromium, aluminum, silver, gold, titanium or an alloy thereof. Theresin includes epoxy resins, bismaleimide triazine (BT) resins,polyimide resins and the like. The resin may include a white pigmentsuch as titanium oxide. Of those materials, a ceramic or composite resinis preferred.

In the case where the base material is formed by such materials, costeffective procurement is possible by application of known manufacturingtechniques.

Examples of the ceramic includes aluminum oxide, aluminum nitride,zirconium oxide, zirconium nitride, titanium oxide, titanium nitride ora mixture thereof. Use of aluminum nitride having high thermal radiationproperty is preferred. The composite resin is preferably a glass epoxyresin. The base material may be rigid to configure to ensure a suitablestrength, and may be flexible.

There is no particular limitation in relation to the shape, dimensions,thickness or the like of the base material in one light emitting device,and such features may be suitably set. The shape of the first mainsurface (flat surface) for example can be a circular, or a polygonalshape such as a quadrilateral, or the like, a rectangle is preferred. Itis preferred that the dimensions are such that the planar area that islarger than the light emitting element as described below. Inparticular, it is preferred that the dimensions have a length of 2 to 5times that of one side of the light emitting element. The thickness isabout 50 to 300 microns.

Connection Terminal

The pair of connection terminals formed at least on the first mainsurface of the substrate. A portion of the edge portion of theconnection terminal is preferably formed to coincide with a portion ofthe edge portion of the first main surface of the substrate. In otherwords, it is preferred that a portion of the end surface of theconnection terminal and a portion of the end surface of the substrateare formed on the same plane. In this manner, the mountingcharacteristics of the light emitting device in a side-view typemounting can be enhanced. In this context, the same plane means thatthere is no unevenness or almost none, but means that an unevenness ofthe level of several microns to several tens of microns is allowable.The means of “coincide with” and “same plane” apply hereafter in thespecification.

The connection terminal includes an element connection portionconfigured to connect with the electrode of the light emitting element(reference is made to 3 c on FIG. 15) and an outer connection portionconfigured to connect with an external unit of the light emitting device(reference is made to 3 b in FIG. 2 and FIG. 15), on the first mainsurface. The outer connection portion preferably extends onto the secondmain surface in addition to the first main surface of the substrate. Forexample, it is preferred that the connection terminal is provided toextend from the first main surface onto the surface that is presentbetween the first main surface and the second main surface (that is tosay, the end surface), or is provided to extend from the first mainsurface onto the end surface that is present between the first mainsurface and the second main surface, and then onto the second mainsurface (for example, a U shape when viewed in cross section) (referenceis made to the connection terminal 3 in FIG. 2, and the connectionterminal 43 in FIG. 8C). The end surface in this context means the wholeor a portion of one end surface that is present between the first mainsurface and the second main surface. However in addition to a portion orthe whole of a specific end surface that is present between the firstmain surface and the second main surface, a portion of the one or twoend surfaces that are closely adjacent to the specific end surface mayalso be included.

Normally, the element connection portion is disposed on the first mainsurface, and the outer connection portion is disposed on (i) the firstmain surface, (ii) the first main surface and the end surface, or (iii)the first main surface, the end surface and the second main surface(reference is made to FIG. 3 and FIG. 15).

The region of connection of the connection terminal with the lightemitting element on the first main surface of the substrate includes aprotruding portion configured to project from the surface of theconnection terminal. This region may be referred to below as the“element connection portion”.

There is no particular limitation in relation to the shape, height,dimensions and the like of the protruding portion, and they can besuitably adjusted considering the size of the substrate, the thicknessof the connection terminal, and the size of the light emitting element.

For example, two protruding portions are preferably arranged with ashape, size and position to respectively correspond to the pair ofrespective electrodes that is formed on the light emitting element asdescribed below.

The planar shape of the protruding portion includes a circle, oval or aring, a polygonal shape such as a triangle or quadrilateral, a shape inwhich the angles of those shapes are rounded, a polygonal shape such asthe letters X, L, E, V, or the like, or a shape in which the angles ofthose letters are rounded. Of those shapes, it is preferred that atleast a portion of the external shape in a plan view of the protrudingportion is a shape that corresponds to the outer shape of the electrodeof the light emitting element. In this manner, as described below, themounting performance can be enhanced due to the effect ofself-alignment. Furthermore, it is preferred that a side of a polygon isconfigured with a shape which is indented in an inner side thereof suchas the shape of an X (the central portions of sides are indented).Accommodation of molten material in the indented portion can be therebyfacilitated, and therefore the mounting of the light emitting elementcan be stabilized.

It is preferred that the inclination on the side surface of theprotruding portion is nearly vertical. In this manner, when the lightemitting element is disposed on the protruding portion and connected bymolten material, movement of the light emitting element that is disposedthereon is impeded, and the mounting of the light emitting element canthereby be stabilized.

The regions of connection with the light emitting element with the pairof connection terminals are normally separated at least on the firstmain surface of the substrate. The protruding portion may be disposedclosely adjacent to the edge portion of the connection terminal, orseparated from the edge portion, and may be partially in proximity andpartially separated. Of those configurations, it is preferred thatentire edge portion of the protruding portion is separated from the edgeportion of the connection terminal and disposed on an inner side of theconnection terminal. (For example, reference is made to the protrudingportion 3 a in FIG. 3, the protruding portion 13 a in FIG. 5A, and theprotruding portion 43 a in FIG. 8E and FIG. 9E). In case where theprotruding portion is disposed in this manner, even if molten materialin a molten state as described below flows from the protruding portionduring mounting process of the light emitting element, the material canbe accommodated in the periphery of the protruding portion, shorting ofthe pair of connection terminals by the molten material and penetrationof the molten material into an unintended area can be prevent, andaccurate fixation of the light emitting element to the desired positionis enabled. Furthermore, it is possible to inhibit solder for mountingof the light emitting device or flux contained therein from penetratingalong the connection end surface under the light reflecting memberdescribed below to under the light emitting element.

The height of the protruding portion should protrude from the region atwhich the film exhibits minimum thickness on the connection terminal onthe first main surface of the substrate, and is preferably at least 10%,at least 20%, at least 30%, at least 40%, at least 50%, or at least 100%of the thickness of the region at which the thin film exhibits minimumthickness. In other words, the thickness of the protruding portion isabout 1 to 40 microns when the thickness of the thin film portion of theconnection terminal on the first main surface exhibits a minimumthickness of normally 10 to 40 microns.

The connection terminal for example can be formed by a single layer ormultiple layers of a metal such as Au, Pt, Pd, Rh, Ni, W, Mo, Cr, Ti,Fe, Cu, Al, Ag, or an alloy thereof. Of those configurations, aconfiguration that exhibits good conductive and mounting properties ispreferred. A material is preferred that exhibits good wettability andconnection performance with the molten material (for example, thesolder) that is used during mounting of the light emitting device. Inparticular, copper or a copper alloy is preferred in view of thermalradiation properties. A covering film may be formed on the surface ofthe connection terminal with high light reflective properties by use ofsilver, platinum, tin, gold, copper, rhodium, or an alloy thereof. Themultiple layers of the connection terminal include W/Ni/Au, W/Ni/Pd/Au,W/NiCo/Pd/Au, and the like.

The connection terminal may include partial differences in relation tothickness or the number of layers (reference is made to the connectionterminal 43 in FIG. 8B and FIG. 9B, and the protruding portion 43 a ofFIG. 8C and FIG. 9C).

The connection terminal may use wiring, a lead frame or the like, andmay be formed by using vapor deposition, a sputtering method, plating orthe like onto the surface of the base material. Of those methods, theuse of plating is preferred. In particular, after formation of a singlefilm or multilayer film of a metal or alloy as described above at leaston the first main surface, the protruding portion can be formed byforming a further layer being a single layer or multiple layers of metalor alloy, by use of a mask, on the single layer or multiple layers.Also, after formation of a thick film by use of plating or the like ontothe surface of the substrate, the protruding portion may be formed byremoving a portion other than the protruding portion by use of etching.This method may achieve a nearly vertical configuration in relation tothe gradient of the side surface of the protruding portion. Even in casewhere using an aggregate substrate describer later, since a deviation inthe plating thickness (height of the protruding portion) can be reduced,production characteristics can be enhanced.

The thickness of the connection terminal can be of several microns toseveral hundreds of microns.

The connection terminal may be the same width (for example, the lengthin the shorter dimension of the substrate) at the first main surface,the end surface and/or the second main surface, and may be partiallyformed with a small or large width. Alternatively, a portion of theconnection terminal may be covered by an insulating member (for example,the base material or a solder resist) described below to form a smallwidth on the first main surface and/or the second main surface of thesubstrate. The small width portion is preferably disposed at least onthe first main surface of the substrate (reference is made to theconnection terminal 3 in FIG. 3), and may be disposed on both of thefirst main surface and the second main surface (reference is made to theconnection terminal 43 in FIG. 8D and FIG. 8F). In particular, the smallwidth portion is preferably disposed in proximity to the lightreflecting member described below on the first main surface of thesubstrate. The disposition of the small width portion makes it possibleto inhibit solder as described below, or flux contained therein, that isconnected with the connection terminal, from penetrating along thesurface of the connection terminal under the light reflecting memberdescribed below to under the light emitting element.

Furthermore, separation of the element connection portion from the endsurface that is oriented along the longitudinal direction of thesubstrate, makes it possible to inhibit solder as described below, orflux contained therein, during mounting of the light emitting device,from penetrating along the connection terminal under the sealing memberdescribed below to under the light emitting element.

The small width portion preferably has a smaller width than the elementconnection portion. Furthermore, the small width portion preferably isconfigured the small width with smoothly (for example, reference is madeto the connection terminal 43 in FIG. 8E).

In case where the connection terminals extend respectively from thefirst main surface to the second main surface, the extension may beconfigured on the end surface or may be via a through hole provided inthe base material.

In addition to the connection terminal that is electrically connected tothe light emitting element, a thermal radiation terminal, a heat sink, areinforcing member, or the like may be included in the substrate(reference is made for example to the reinforcing member 43 c in FIG. 8Band FIG. 9B). These features may be disposed on either of the first mainsurface, the second main surface and the end surface of the substrate.In particular, such member is preferably disposed below the lightemitting element and/or the light reflecting member. In this manner, thestrength of the light emitting device is enhanced and reliability can beimproved. Furthermore, when the light reflecting member is formed by useof a molding die, distortion of the substrate can be reduced and themolding characteristics of the light reflecting member can be enhanced

In case where the thermal radiation terminal or the reinforcing memberthat made from metal is provided in the interval between connectionterminals, it is preferred to cover by an insulating member describedbelow such as a solder resist, or the like, or to provide an insulatingfilm between the respective connection terminals. In this manner, abridge of molten material between the connection terminal and thethermal radiation terminal or the reinforcing member can be prevented.

In case where a plurality of light emitting elements is disposed on asingle light emitting device, at least one further connection terminalmay be provided to electrically connect the plurality of light emittingelements. In this configuration, the number of the light emittingelements mounted on a single substrate, their arrangement, connectionconfiguration (parallel or series), or the like can be suitably selectedby setting of the shape and position of the connection terminal(reference is made to the terminal 25 in FIG. 6B). This additionalconnection terminal may include the protruding portion as describedabove at a position for connection with the light emitting element.

The upper surface of the protruding portion or the first main surfaceother than the protruding portion of the connection terminal ispreferably flat. Furthermore, when the light emitting element is mountedonto the substrate, it is preferred that the surface of the protrudingportion and the first main surface of the connection terminal arehorizontal with respect to the first main surface of the substrate sothat the light emitting surface can be disposed horizontally.

The substrate may itself constitute a capacitor, a varistor, a Zenerdiode, a bridge diode, or another such protective element, or it maypartially include a structure that provides the functions of theseelements. If a substrate that has these element functions is used, thelight emitting device will be able to function without any special partsbeing mounted, so a high-performance light emitting device with enhancedelectrostatic withstand voltage can be made more compact.

Light Emitting Element

The light emitting element is mounted on the substrate, and is connectedwith the connection terminal on the first main surface of the substrate.

One light emitting element or a plurality of light emitting elements canbe mounted on one light emitting device. The size, shape and lightemission wavelength of the light emitting element may be suitablyselected. In case where a plurality of light emitting elements ismounted, the arrangement may be irregular, or may have a regular orcyclical configuration such as a matrix arrangement or the like. Theplurality of light emitting elements may have a connection configurationsuch as a series, parallel, serial parallel, or parallel series.

The light emitting element of the present light emitting device isproduced as a semiconductor laminate that stacked a first semiconductorlayer (such as an n-type semiconductor layer), a light emitting layer,and a second semiconductor layer (such as a p-type semiconductor layer),in that order, for example. On one side (also referred to as the secondsemiconductor layer side, for example) of the semiconductor laminate, afirst electrode that is connected to the first semiconductor layer, anda second electrode that is connected to the second semiconductor layerare disposed. The semiconductor laminate is usually laminated over anelement substrate used for growing a semiconductor layer, and may retainthis substrate, or the substrate may be removed in final light emittingelement.

There are no particular restrictions on the kind and material of thesemiconductor laminate. Examples thereof include various kind ofsemiconductor such as a III-V compound semiconductor, a II-VI compoundsemiconductor. More specifically, examples thereof include anitride-based semiconductor material such as In_(X)Al_(Y)Ga_(1-X-Y)N(0≤X, 0≤Y, X+Y≤1), InN AlN, GaN, InGaN, AlGaN, InGaAlN, and the like canbe used. A known a thickness or a laminated structure of each layer inthe art can be used.

The element substrate may be one which can be grown semiconductor layersthereon. Examples of the material for the element substrate include aninsulating substrate such as sapphire (Al₂O₃) and spinel (MgAl₂O₄) andthe like, and a semiconductor, substrate such as the nitridesemiconductor described above. In case where a transparent substratesuch as sapphire is used for the element substrate, the elementsubstrate may be employed in the light emitting device without removingfrom the semiconductor laminate.

The element substrate may have convexes and concaves on its surface.

The surface of the element substrate may have an off angle of about 0 to10° with respect to a crystalline surface such as C plane or A plane.The substrate may have at least one semiconductor layer such as anintermediate layer, buffering layer, underlying layer, and the like, orat least one insulating layer.

The element substrate for growth of the semiconductor layer can beremoved by use of a laser lift off method by illuminating laser light,that passes through the element substrate (for example, a KrF excimerlaser), from the element substrate side for growth onto thesemiconductor layer to produce a decomposition reaction on the interfacebetween the semiconductor layer and the element substrate and therebyseparate the element substrate from the semiconductor layer. However,the element substrate for growth of the semiconductor layer may becompletely removed from the semiconductor layer, or some portion of theelement substrate may remain in the corner portions or end portions ofthe semiconductor layer. The removal of the element substrate may beperformed before or after the mounting of the light emitting element onthe substrate of the light emitting device.

If the element substrate used for growing a semiconductor layer isremoved from the semiconductor laminate, the resulting light emittingdevice will be thinner and more compact. Also, removing any layers thatdo not contribute directly to light emission prevents the light emittedfrom the light emitting layer from being absorbed by these layers, soemission efficiency can be increased. As a result, brighter light can beemitted.

There are no particular restrictions on the shape of the semiconductorlaminate in a plan view, but a shape that is quadrangle or a similarshape is preferable. The upper limit to the size of the semiconductorlaminate can be suitably adjusted according to the size of the lightemitting device. More specifically, an example of the length of thesemiconductor laminate along one side is from a few hundred microns toabout 10 mm.

First Electrode and Second Electrode

The first electrode and the second electrode of the light emittingelement are formed on the same surface of the semiconductor laminate (incase where the element substrate for growing the semiconductor layer ispresent, the opposite side surface of the element substrate). In thismanner, flip chip mounting can be used that opposes and bonds the firstelectrode and the second electrode of the light emitting element, andthe positive and negative connection terminals of the substraterespectively.

The first electrode and second electrode can be formed by a single-layerfilm or a laminate film of Au, Pt, Pd, Rh, Ni, W, Mo, Cr, Ti, Al, Ag oranother such metal or an alloy of such metals. More specifically, it canbe formed by a laminate film in which Ti/Rh/Au, W/Pt/Au, Rh/Pt/Au,Ni/Pt/Au, Ti/Rh or AlSiCu/Ti/Pt/Au are laminated in that order startingfrom the semiconductor layer side. The film thickness may be thethickness of any film used in this field.

The first electrode and second electrode preferably have a materiallayer whose reflectivity to light emitted from the light emitting layeris higher than that of the other material of the electrodes as part ofthese electrodes on the side closer to the first semiconductor layer andthe second semiconductor layer.

An example of a material with high reflectivity is silver, a silveralloy, aluminum, or an aluminum alloy. The silver alloy may be anymaterial that is known in this field. There are no particularrestrictions on the thickness of this material layer, but an example isa thickness that allows the light emitted from the light emittingelement to be effectively reflected, such as about 20 nm to 1 μm. Thegreater is the contact surface area of this material layer with thefirst semiconductor layer or the second semiconductor layer, the better.

In case where silver or a silver alloy is used, the surface thereof(preferably the top face or end surfaces) is preferably covered with acover layer in order to prevent the migration of the silver. This coverlayer can be formed by a metal or alloy that is used as a single-layerfilm or a laminate film including a conductive material such Al, Cu, Nior another such metal. Among these, AlCu can be used preferably. Thethickness of the cover layer may be from a few hundred nanometers to afew microns, in order to effectively prevent the migration of silver.

As long as the first electrode and second electrode are connected to thefirst semiconductor layer and second semiconductor layer, respectively,the entire surface of the electrodes need not be touching thesemiconductor layer, and part of the first electrode may not be arrangedabove the first semiconductor layer and/or part of the second electrodemay not be arranged above the second semiconductor layer. That is, thefirst electrode may be arranged above the second semiconductor layer,and the second electrode may be arranged above the first semiconductorlayer, via an insulating film or the like. In this arrangement, theshapes of the first electrode and the second electrode are easilychanged, therefore mounting the light emitting element to the connectionterminals can be easy.

There are no particular restrictions on the insulating film, which maybe any single-layer film or laminated film that is used in this field.The first electrode and second electrode can be set to the desired sizeand position, regardless of the surface area of the first semiconductorlayer and/or the second semiconductor layer, by using theabove-mentioned insulating film or the like.

The shape of the first electrode and second electrode can be setaccording to the shape of the semiconductor laminate, the shape of theterminals (in particular, protruding portion), and so forth. Forinstance, the first electrode and second electrode, and the connectionterminals (in particular, the protruding portion) preferably have ashape that is quadrangle or close to quadrangle. Consequently, aself-alignment effect allows for easy positioning and joining of thesemiconductor laminate and the substrate. In this case, it is preferableif the planar shapes of the first electrode and second electrode aresubstantially the same at least at the outermost surface of thesemiconductor laminate connected to the substrate. It is also preferableif the first electrode and second electrode are disposed so as to faceeach other, with the center portion of the semiconductor laminate inbetween in a plan view.

The first main faces of the first electrode and second electrode (thefaces on the opposite side from the semiconductor layer) may have astep, but are preferably substantially flat. The term “flat” here meansthat the height from the second main face of the semiconductor laminateto the first main face of the first electrode, and the height from thesecond main face of the semiconductor laminate to the first main face ofthe second electrode are substantially the same. The phrase“substantially the same” here encompasses variation of about ±10% in theheight of the semiconductor laminate.

The light emitting element will be easier to mount horizontally on thesubstrate if the first main faces of the first electrode and secondelectrode are substantially flat, that is, substantially in the sameplane. To form the first electrode and second electrode in this way, forexample, a metal film is provided by plating or the like over theelectrodes, after which this is polished or cut so that the surfaces liein substantially the same plane.

A DBR (distributed Bragg reflector) may be disposed between the firstelectrode and second electrode and their respective first semiconductorlayer and second semiconductor layer, to the extent that this does notimpair electrical connection of these. A DBR is a multilayer structurein which a low refractive index layer and a high refractive index layerare laminated over an under layer composed of an oxide film or the like,and selectively reflects light of a specific wavelength. Specifically, aspecific wavelength can be reflected very efficiently by alternatelylaminating films of different refractive indexes at a thickness of aquarter of the specific wavelength. The DBR can be formed of layersincluding an oxide film or nitride film selected from Si, Ti, Zr, Nb,Ta, Al or the like.

Molten Material

The first electrode and the second electrode of the light emittingelement are normally bonded with the connection terminal of thesubstrate described above by use of a bonding agent. In the oneembodiment, the first electrode and the second electrode of the lightemitting element are bonded to the connection terminal of the substratedescribed above by a molten material as an bonding agent, and inparticular are bonded onto the protruding portion, and may also bebonded onto the side surface of the protruding portion. The bondingagent and the molten material may be any material that is known in thisfield. More specifically, the bonding agent includes solder such astin-bismuth solder, tin-copper solder, tin-silver solder and gold-tinsolder, or the like, and a conductive pastes of silver, gold, palladium,or the like, a bump, anisotropic conductive materials, and a brazingfiller metal such as low melting point metals, or the like. The moltenmaterial includes materials that are melted by heating, for example, thesolders described above, or a brazing material such as a low meltingpoint metal. The use of solder facilitates mounting of the lightemitting element to a suitable position due to the self-alignmenteffect, enables an increase in manufacturing performance, and enablesthe manufacture of a smaller light emitting device.

The molten material may cover at least the upper surface of theprotruding portion if the light emitting device has the protrudingportion. The molten material may cover the whole or a portion of theside surface of the protruding portion, and the first main surface ofthe connection terminal on the peripheral side of the protrudingportion.

Light Reflecting Member/Sealing Member

The light reflecting member exhibits light reflecting characteristics,and is a member to cover, fix or seal at least the light emittingelement. Furthermore, it embeds the molten material and the protrudingportion of the connection terminal described above. A position on theprotruding portion of the connection terminal that is not covered by themolten material and a position of the molten material that is not incontact with the electrode of the light emitting element, and a positionof the light emitting element facing the substrate and not being incontact with the molten material, and the whole of that side surfacesare preferably placed in contact with and covered by the lightreflective member. This type of arrangement enables light emitted fromthe light emitting element to avoid being absorbed by the substrate, theconnection terminal and the molten material, or the like, and enableslight emitted from the light emitting element to extract efficiently tothe light extraction surface side.

The sealing member is a member that fixes or seals at least the lightemitting element. The sealing member preferably exhibits lightreflecting characteristics, and more preferably has the same function asthe above light reflecting member.

There are no particular restrictions on the material of the lightreflecting member and the sealing member, examples thereof includeceramics, resin, dielectrics, pulp, glass or the its complex material.Among these, a resin is preferable to easily form the desired shape.

Examples of the resin include a thermosetting resin and a thermoplasticresin. Specific Examples of such a resin include an epoxy resincomposition; a silicone resin composition; a modified epoxy resincomposition such as a silicone modified epoxy resin; a modified siliconeresin composition such as an epoxy modified silicone resin; a polyimideresin composition, a modified polyimide resin composition,polyphthalamide (PPA), a polycarbonate resin; a polyphenylene sulfide(PPS); a liquid crystal polymer (LCP); an ABS resin (anacrylonitrile-butadiene-styrene resin); a phenolic resin; an acrylicresin; and a PBT resin (polybutylene terephthalate resin).

The light reflecting member and the sealing member are preferably formedby a material so that its reflectivity of light from the light emittingelement will be at least 60%, and preferably at least, 70%, 80%, or 90%.

Therefore, it is preferred that the above material, for example, theresin include a light reflecting material such as titanium dioxide,silicon dioxide, zirconium dioxide, potassium titanate, alumina,aluminum nitride, boron nitride, mullite, niobium oxide, barium sulfate,various rare earth oxides (e.g., yttrium oxide, gadolinium oxide, etc.),and may be include a colorant such as carbon black and the like.

In this manner, the light from the light emitting element can beefficiently reflected. In particular, the use of a material thatexhibits higher reflectivity than the substrate (for example, in casewhere aluminum nitride is used in the substrate, a silicon resincontaining titanium dioxide is used as the light reflecting member)maintains handling characteristics, enables downsizing of the substrate,and further increases the light extraction efficiency of the lightemitting device.

The light reflecting member and the sealing member may also contain afibrous filler such as glass fibers, wollastonite, an inorganic fillersuch as carbon, or the like. The light reflecting member and the sealingmember may contain a material having a high heat dissipation such asaluminum nitride and the like. Further, the light reflecting member andthe sealing member may include a fluorescent material described below.In case where these additives are used, it is preferably to contain 10to 40 weight % with respect to the total weight of the light reflectingmember and the sealing member.

In this manner, It is possible to reinforce the light reflecting memberduring processes such as the removal and peeling of the substrate foruse of growth of the semiconductor layer, or the like, and/or the lightemitting device.

Furthermore, the use of a material having high thermal radiationcharacteristics is adapted to enable downsizing of the light emittingdevice and to enhance thermal radiation characteristics.

There is no particular limitation in relation to the shape of the lightreflective member and the sealing member, and for example it includespolygonal columnar configurations such as circular cylinders, squarecolumns, or the like, or shapes approximate thereto, or polygonaltruncated configurations such as truncated cones, truncated pyramid, orthe like. Of those shapes, a shape are preferred that elongates withreference to the longitudinal direction of the substrate. Furthermore,it is preferred that a surface is provided along the short direction ofthe substrate.

The light reflective member or the sealing member are preferablyprovided to surround the entire periphery (side surfaces) of the lightemitting element. Furthermore it is preferred that the member isprovided to fill the space between the substrate and the light emittingelement mounted in a flip chip manner. In this manner, the strength ofthe light emitting device can be increased. In case where providing thelight reflective member and the sealing member to surround the entireperiphery (side surfaces) of the light emitting element, the lightreflective member and the sealing member preferably form a thick inrelation to the longitudinal direction of the light emitting device anda thin in relation to the short direction. In this manner, the width ofthe light emitting device can reduced. In the one embodiment, the lightreflective member or the sealing member are preferably contacted with aninsulating member described below, and is provided between the lightemitting element and the insulating member.

The edge portion when viewed in a plan view of the light reflectivemember or the sealing member may be disposed at a position furtheroutside or inside of the edge portion of the substrate. In case wherethe light reflective member or the sealing member have a shape that iselongated in relation to a longitudinal direction of the substrate, oneedge portion along the longitudinal direction preferably coincides withthe edge portion along the longitudinal direction of the substrate. Thatis to say, at least one of the end surface along the longitudinaldirection of the light reflective member or the sealing memberpreferably form a coplanar surface with one of the end surface along thelongitudinal direction of the substrate. It is still more preferred thatboth of the end surfaces along the longitudinal direction of the lightreflective member and the sealing member form a coplanar surface withboth of the end surfaces along the longitudinal direction of thesubstrate. In this manner, the surface area of the light extractionsurface can be increased without increasing in the width of the lightemitting device, and therefore it is possible to increase the lightextraction efficiency of the light emitting device. The edge portionalong the short direction of the light reflecting member or the sealingmember may be disposed on an outer side with reference to the edgeportion along the short direction of the substrate and may be disposedon an inner side.

In case where the light emitting device is mounted in a side-view typeconfiguration, the width in the short direction of the light reflectingmember or the sealing member and the substrate is preferably 0.2 mm to0.4 mm.

The size of the light reflective member and the sealing memberpreferably is configured with a larger surface area than the lightemitting element, and in particular it is preferred to exhibit a size inwhich the length of one side is 2 to 5 times that of one side of thelight emitting element. The thickness for example is of the order of 50to 300 microns.

The light reflective member and the sealing member may be formed byscreen printing, potting, transfer molding, compression molding, or thelike.

The light reflective member and the sealing member may be provided tocover the upper surface or the side surface of the light emittingelement prior to mounting of the light emitting element on thesubstrate. However, it is preferred to perform formation after mountingof the light emitting element on the substrate in order to seal or coverthe surface of the light emitting element that faces the substrate, andthe whole surface on the side surface of the light emitting element.

Insulating Member

In the one embodiment, the light emitting device preferably includes aninsulating member.

The insulating member is preferably placed in contact with the lightreflecting member or the sealing member, is disposed to cover at least aportion of the connection terminal, and is disposed between the elementconnection portion and the outer connection portion of the connectionterminal. In this manner, as described below, when mounting the lightemitting device on the mounting board, it is possible to avoidpenetration of solder along the surface of the connection terminal andthereby avoid a reduction in the reliability of the light emittingdevice.

It is preferred that the insulating member is disposed to totallyseparate the surface region of the connection terminal between theelement connection portion and the outer connection portion.Furthermore, it is preferred to dispose on the connection terminal sothat the edge portion of the light reflecting member or the sealingmember is disposed on the insulating member. In this manner, theadhesion property between the light reflecting member or the sealingmember and the substrate can be enhanced, and a risk of peeling of thelight reflecting member or the sealing member can be reduced. Inparticular, as described above, in case where the light reflectingmember or the sealing member has a shape that is elongated withreference to the longitudinal direction, it is preferred that the edgeportion in the longitudinal direction of the light reflecting member orthe sealing member is disposed on the insulating member that disposed onthe connection terminal. Consequently, that when the substrate becomeswarped or bent, the risk of peeling of the light reflecting member orthe sealing member can be reduced. Furthermore, as described above, theconnection terminal may not always be configured with the same width onthe first main surface, and therefore a portion of the insulating membermay be disposed not only on the connection terminal but also on the basematerial.

A pair of insulating members may be provided to respectively cover thepair of connection terminals, or may be configured to connect and coverthe pair of connection terminals.

As long as the insulating member exhibits insulating properties,formation by use of any appropriate material is possible. For example, amaterial given by example in relation to the light reflecting member andthe sealing member described above, or the light transmissive memberdescribed below can be used. Of those materials, a white silicon resinthat has high heat resistance performance is preferred.

There is no particular limitation on the shape of the insulating member.However it is preferred that formation is in the shape of a bandconnected from the adjacent position to the element connection portionto the outer side of the light reflecting member and the sealing member,that is to say to the outer connection portion.

More specifically, the length of the insulating member in thelongitudinal direction can be a length of 1/10 to/⅕ of the lightreflecting member and the sealing member.

It is preferred that the width of the insulating member is the same asthe width of the substrate and/or the light reflecting member or thesealing member.

That width enables a surface of the insulating member to be coplanarwith one end surface of the substrate and/or the light refracting memberor the sealing member, and furthermore enables two opposing surfaces ofthe insulating member to be coplanar with end surfaces of each of thesubstrate and the sealing member.

In particular, in case where there is a position at which the connectionterminal is configured with a small width, it is preferred that theposition having the small width is completely covered with theinsulating member. In this manner, as described below, penetration ofsolder along the connection end surface and the resulting adverse effecton the reliability of the light emitting device can be avoided whenmounting the light emitting device on the mounting board.

The insulating member can be formed by a method of adhering a materialas described above in a sheet configuration, a printing method, anelectrodeposition method, potting, compression molding, spraying, anelectrostatic coating method, or the like.

There is no particular limitation on the thickness of the insulatingmember, and for example, it may be configured at about 10 to 300microns.

When using a die to mold the light reflecting member or the sealingmember, the insulating member is preferably formed by connection frombelow the light reflecting member and the sealing member to the outerconnection portion side. In this manner, it is possible to preventcontact of the die used for molding of the light reflecting member andthe sealing member with the connection terminal and therefore avoiddamage to the connection terminal.

Light Transmissive Member

It is preferred that the light transmissive member is disposed on thelight extraction surface of the light emitting device to cover the lightextraction surface of the light emitting element.

The light transmissive member may be formed by the same member as thelight reflecting member and the sealing member, or may be a differentmember.

The end surface of the light transmissive member may coincide with theend surface of the light reflecting member or the sealing member, or theend surface of the light transmissive member may be covered by the lightreflecting member or the sealing member. The disposition of the lighttransmissive member in this manner enables light extracted from thelight emitting element to be introduced efficiently to the lightemitting surface.

The light transmissive member allows penetration of light, which is 60%or greater of light emitted from the light emitting layer, and furtherpreferably allows penetration of 70% or greater, 80% or greater, or 90%or greater of light emitted from the light emitting layer. Such membercan be formed by a material such as a resin, for example, a siliconeresin, a modified silicone resin, an epoxy resin, a modified epoxy resinphenolic resin, polycarbonate resin, acrylic resin, TPX resin,polynorbornene resin, or hybrid resin containing one or more of theseresins, and glass and the like. Of those materials, use of a siliconresin that exhibits good heat resistance and light resistance ispreferred.

It is preferred that a fluorescent material is included in the lighttransmissive member.

As the fluorescent material that is known in this technical field can beused, and includes for example, a YAG-based fluorescent materialactivated by cerium, LAG-based fluorescent material activated by cerium,a carcium aluminosilicate containing nitride fluorescent materialactivated by europium or chromiun (CaO—Al₂O₃—SiO₂), a silicatefluorescent material activated by europium (Sr,Ba)₂SiO₄),beta sialonfluorescent material, KSF fluorescent material (K₂SiF₆:Mn), minutesemiconductor particles that are termed quantum dot fluorescentmaterial, and the like. In this manner, it is possible to obtain a lightemitting device that emits mixed colored light containing a primarylight and a secondary light in visible wavelengths (for example, whitelight), and to obtain a light emitting device that is excited byultraviolet primary light to thereby emit secondary light in visiblewavelengths. In case where the light emitting device is used in abacklight for a liquid crystal display, use is preferred of afluorescent material excited by blue light emitted from the lightemitting element to thereby emit red light (for example, a KSFfluorescent material), and a fluorescent material that emits green light(for example, beta SiAlON fluorescent material). In this manner, thecolor reproduction range of the display can be increased.

The fluorescent material is not limited to inclusion in the abovemembers, and may be provided in a variety of positions and members inthe light emitting device. For example, formation is possible to coverthe light emitting element without the light transmissive member and maybe provided as a fluorescent layer coated and adhered onto the lighttransmissive member that does not contain the fluorescent material.

The light transmissive member may further include filling agent (forexample, a dispersing agent, a coloring agent, and the like). Examplesthereof include silica, titanium oxide, magnesium oxide, magnesiumcarbonate, magnesium hydroxide, calcium carbonate, calcium hydroxide,calcium silicate, zinc oxide, barium titanate, aluminum oxide, ironoxide, chromium oxide, manganese oxide, glass, carbon black. Therefractive index of the filling agent may be adjusted as required, andfor example includes at least 1.8, with at least 2 being preferred andat least 2.5 being more preferred in order to obtain high lightextraction efficiency by efficient refraction of light.

The shape of the particles of the filling agent may be any of granular,spherical, hollow, porous, or the like. The average particle diameter(median diameter) of the particles is preferably about 0.08 to 10microns in order to obtain a highly efficient light dispersal effect.

The filling agent for example is preferably about 10 to 60 wt % relativeto the weight of the light transmissive member.

A method for forming the light transmissive member is a method byforming a sheet of the light transmissive member and attaching it usinghot-melt adhesive or an adhesive agent, potting, compression molding,spray, electrostatic coating, printing and the like. Silica (aerogel)may be added to the light transmissive member in order to adjustviscosity or flowability.

There is no particular limit on the thickness of the light transmissivemember and for example may be configured at about 10 to 300 microns.This thickness setting enables light extracted from the light emittingelement to be guided efficiently to the light emitting surface of thelight emitting device even when the end surface of the lighttransmissive member coincides with the end surface of the lightreflecting member, or even when covered by the light reflecting member.

The light transmissive member may be configured with the first mainsurface and/or the second main surface as an uneven surface such as aprotruding surface or a recessed surface in order to control the lightdistribution.

The light transmissive member can be adhered to the upper surface of thelight emitting element before mounting of the light emitting elementonto the substrate and set on the light emitting device. In particular,in case where the light emitting element is configured by asemiconductor laminated body in which the element substrate for growthof the semiconductor layer is removed, for example, the strength of thelight emitting element is increased by adhesion or fixing to a hardlight transmissive member such as glass, ceramic, or the like, andtherefore the reliability of the mounting of the light emitting elementand the handling performance can be increased.

The light emitting device of the present disclosure will now bedescribed in detail through reference to the drawings.

First Embodiment

As illustrated in FIG. 1 to FIG. 3, the light emitting device 1 of thepresent embodiment has a substrate 4 that has a connection terminal 3, alight emitting element 5, and a light reflective member 7.

The substrate 4 has a pair of connection terminals 3 formed bylaminating Cu/Ni/Au from the base material 2 side onto the surfaces (theupper surface 2 a that is the first main surface, and end surfaces 2 bthat extend in the direction of the short dimension, and the lowersurface 2 c that is the second main surface) of the rectangularparallelepiped base material 2 that is formed by a glass epoxy resin.The substrate 4 is served as a wiring base and has a length in alongitudinal direction of 2.2 mm, a width in the short dimensiondirection of 0.4 mm and a thickness of 0.3 mm.

The pair of connection terminals 3 includes protruding portions 3 aserved as an element connection portion in a mutually adjacentconfiguration on a central portion of the upper surface 2 a side of thebase material 2. The protruding portion 3 a is formed by laminatingCu/Ni/Au from the base material 2 side. The pair of connection terminals3 extends respectively from the protruding portion 3 a that is theelement connection portion in the longitudinal direction, from the uppersurface 2 a of the base material 2 through respective end surface 2 b tolower surface 2 c of the substrate. A portion of the each connectionterminals 3 that is positioned to extend from the protruding portion 3 athat is the element connection portion and to connect with the lowersurface 2 c of the base material 2 (position in the shape of a letter Uwhen viewed in cross section) is served as the outer connection portion3 b (reference is made to FIG. 2).

The edge portion along the longitudinal direction of each the connectionterminal 3 (specifically the outer connection portion) coincides withthe edge portion along the longitudinal direction of the substrate 4,and the end surface along the longitudinal direction of the connectionterminal 3 (specifically the outer connection portion) is formedcoplanar with the end surface along the longitudinal direction of thesubstrate 4.

Each the connection terminal 3 includes a small width portion betweenthe protruding portion 3 a that is the element connection portion andthe outer connection portion 3 b (reference is made to FIG. 3). Aportion of the outer connection portion 3 b on the second main surfaceof the substrate 4 includes a small width portion.

A light emitting element 5 is mounted on the protruding portion 3 a ofthe substrate 4 in flip chip manner.

The light emitting element 5 includes a laminated body (semiconductorlaminate) of a nitride semiconductor formed on a sapphire substrate, anda pair of positive/negative electrodes on the surface that is oppositeto the sapphire substrate of the laminated body. The pair ofpositive/negative electrodes of the light emitting element 5 isconnected by the molten material 6 that is an Au—Sn eutectic solder tothe protruding portions 3 a of the pair of connection terminals 3 on thesubstrate 4.

In case where the protruding portion 3 a of the connection terminal isused in this manner, even if molten material 6 in a molten configurationas described below flows from on top of the protruding portion duringmounting of the light emitting element, the material can be accommodatedin the periphery of the protruding portion, and shorting of the pair ofconnection terminals and penetration of the molten material into anunintended area can be prevented. Therefore accurate fixation of thelight emitting element to the target position is enabled.

The light emitting element 5 is an LED chip that emits blue light(central emission wavelength of 455 nm) in a rectangular parallelepipedconfiguration with a length in a longitudinal direction of 0.8 mm, awidth in the short direction of 0.3 mm and a thickness of 0.1 mm.

The light reflecting member 7 is formed substantially in a rectangularparallelepiped configuration with a length in a longitudinal directionof 1.2 mm, a width in the short direction of 0.4 mm and a thickness of0.3 mm. The edge portions along the longitudinal direction of the lightreflecting member 7 respectively coincides with the edge portions alongthe longitudinal direction of the substrate 4.

The light reflecting member 7 is provided on the first main surface ofthe substrate 4 in contact with the light emitting element 5 and tothereby cover the entire periphery of the end surface of the lightemitting element 5. Furthermore, the light reflecting member 7 is alsoprovided on the side of the surface facing the substrate 4 of the lightemitting element 5. That is to say, disposition of the light reflectingmember 7 is performed in the interval with the molten material 6 thatsubstantially completely covers the protruding portion 3; andsubstantially completely covers the surface of the molten material 6. Inthis manner, efficient light extraction is enabled on the upper surfacefrom the light emitting element 5.

The light reflecting member 7 is formed by a silicon resin containssilica having an average particle diameter of 14 microns and titaniumoxide having an average particle diameter of 0.25 microns to 0.3 micronsare respectively composed as 2 to 2.5 wt % and 40 to 50 wt % relative tothe total weight of the light reflecting member 7.

A portion of the small width portion of the connection terminal 3 and aportion of the outer connection portion are exposed from the lightreflecting member 7 on both sides of the light reflecting member 7 onthe substrate 4. The edge portion along the longitudinal direction ofthe light reflecting member 7 coincides with the edge portion along thelongitudinal direction of the substrate 4, and the end surface along thelongitudinal direction of the light reflecting member 7 is formedcoplanar with the end surface along the longitudinal direction of thesubstrate 4.

A light transmissive member 10 configured as a sheet of silicon resin(thickness 0.1 mm) that includes a YAG:Ce fluorescent material isdisposed on the light emitting element 5, that is to say, on the surfaceopposite the pair of positive and negative electrodes.

The end surface of the light transmissive member 10 is covered by thelight reflecting member 7. The upper surface of the light transmissivemember 10 and the upper surface of the light reflecting member 7 areformed in a coplanar configuration.

As illustrated in FIG. 4, the pair of end surfaces along thelongitudinal direction of the substrate 4 and the pair of end surfacesalong the longitudinal direction of the light reflecting member 7 of thelight emitting device 1 are disposed respectively in a coplanarconfiguration. One of the end surfaces in the coplanar configuration 52and is configured as a mounting surface of the light emitting device 1,and is mounted in a side-view configuration on the mounting board 51that has a surface wiring pattern.

The mounting of the light emitting device 1 is configured so that thepair of outer connection portions 3 b of the light emitting device 1 isrespectively disposed on the wiring pattern 52 corresponding to thepositive and negative electrodes of the mounting board 51, and isconnected by solder 54. The solder 54 extends over the end surface andthe second main surface in addition to the first main surface of thesubstrate 4 on the outer connection portion 3 b that is curved in theshape of the letter U. In this manner, a fillet can be formed on theside surface of the light emitting device and thereby enhances themounting stability and thermal radiation performance of the lightemitting device.

In this embodiment, small width portion between the protruding portion 3a and the outer connection portion 3 b on the connection terminal 3suppresses penetration of solder or the like as described above and fluxor the like contained therein that are connected with the outerconnection portion 3 b under the light reflecting member 7.

Both one of the end surface along the longitudinal direction of thesubstrate 4 and one of the end surface along the longitudinal directionof the light reflecting member 7 are in contact with the surface of themounting board 51.

In this embodiment, the light reflecting member 7 itself is providedwith an extremely thin wall configuration on the periphery of the lightemitting element 5, and therefore it is possible to downsize the lightemitting device. Furthermore, the disposition of the light reflectingmember 7 in contact with the periphery of the light emitting elementenables extraction of light emitted in a horizontal direction of thelight emitting from the light emitting element for reflection in anupward by the light reflecting member 7. Therefore, the use efficiencyof the light can be enhanced.

As illustrated in FIG. 5A and FIG. 5B, the light emitting device 1enables manufacture by use of an aggregate substrate 14 that forms anaggregate connection terminal 13 on the base material 12. The aggregatesubstrate 14 is configured by connection of a plurality of units thatform the substrate of each light emitting device after the processing ofunit formation.

In this embodiment, the aggregate substrate 14 includes slits 15 fromthe upper surface to the lower surface on the base material 12. Theaggregate connection terminal 13 is provided on the upper surface andthe lower surface of the base material 12 of the aggregate substrate 14through the inner wall of the slit 15.

Although FIG. 5 shows the aggregate substrate 14 which forms eighteenlight emitting devices, the aggregate substrate 14 can be configured toform more numerous (several hundred to several thousand) light emittingdevice 1A when manufacture efficiency is considered.

A plurality of insulated member are formed on the aggregate substrate 14in a single operation. Then a plurality of light emitting element 5 areconnected on the aggregate substrate 14, and a plurality of lighttransmissive member 10, that has substantially the same shape as thelight emitting element 5 when viewed in plan, is adhered onto the uppersurface of each light emitting element 5. A plurality of lightreflecting members 17 is formed in a single operation by use ofcompressive molding to cover the end surface of the light transmissivemember and the light emitting element. Then the aggregate substrate 14and the light reflecting member 17 are cut in a single direction alongthe predetermined dividing lines L which intersect with the slits 15 atsubstantially right angles. In this manner, division along the directionof extension of the slits 15 is enabled to obtain a plurality ofsingulated light emitting devices separated into units in comparativelyfew processing steps.

A dicer, a laser, or the like can be used in the cutting process.

Second Embodiment

As illustrated in FIG. 6, the light emitting device 20 according to thisembodiment includes a substrate 24 that has a connection terminal 23, aplurality of light emitting elements 5, and a light reflecting member27.

The connection terminal 23 is disposed to extend to the upper surface,the end surface and the lower surface on both sides in the longitudinaldirection of the base material 22. Furthermore, a plurality of lightemitting elements 5 is connected for example in series and furtherterminals 25 are disposed on the upper surface of the base material 22.

The connection terminal 23 and the further terminals 25 on the samesurface of the substrate 24 respectively include the protruding portions23 a as an element connection portion, and the light emitting elements 5are connected by molten material 6 on the protruding portions 23 a.

In this embodiment, a plurality of light emitting elements 5 is disposedby alignment into a line. Arrangement is also possible into a matrixconfiguration.

The light reflecting member 27 integrally cover the plurality of lightemitting element 5. Each end surface along the longitudinal direction ofthe light reflecting member 27 is formed coplanar with each end surfacealong the longitudinal direction of the substrate 24. Each edge portionfacing the short direction of the light reflecting member 27 is disposedon the inner side of the substrate 24.

It is preferred that a recessed portion or through hole is formed in thesubstrate 24 between the light emitting elements 5, and a portion of thelight reflecting member 27 is filled into the recessed portion or thethrough hole to thereby fix the light reflecting member 27 to thesubstrate 24. In this manner, the adhesion property between the lightreflecting member 27 and the substrate 24 are enhanced, and it ispossible to prevent peeling of the light reflecting member 27 from thesubstrate 24.

Features other than those described above are substantially the same asthe first embodiment, and therefore the same effect as the firstembodiment can be imparted.

Furthermore, the light emitting device can be used as a linear or matrixtype side-view light emitting device. Therefore, the light emittingdevice enhances mounting accuracy in comparison to mounting individualside-view light emitting devices on a mounting board respectively.Furthermore, alignment characteristics with the light guide plate areenhanced when functioning as a backlight light source for example.

Third Embodiment

As illustrated in FIG. 7, the light emitting device 30 according to thepresent embodiment is configured by arranging a plurality of lightemitting device according to the first embodiment, that is to say, alight emitting device including a protruding portion 33 a as an elementconnection portion on the pair of connection terminal 33, into thedirection of a row or a matrix, in a configuration that the lightemitting devices are connected each other so that they share theadjacent connection terminals 33, and in particular the outer connectionportion 33 b. Through holes are provided in the base material 32 betweenadjacent light emitting elements 5, and a plurality of connectionterminal 33 of the substrate 34 is drawn towards the lower surface sideof the substrate 34 through the through holes.

Features other than those described above are similar to the firstembodiment. Therefore, the same effect as the first embodiment and thesecond embodiment can be imparted.

Fourth Embodiment

As illustrated in FIG. 8A to FIG. 8G, the light emitting device 40according to the present embodiment includes a connection terminals 43extends from the first main surface of the base material 42 throughrespective end surface to the second main surface, is formed by Cu/Ni/Au(thickness 20 microns), further includes a layer of Cu (thickness 20microns) on the first main surface and the second main surface, andfurthermore includes a protruding portion 43 a of Cu as a connectionterminal portion (thickness 40 microns).

The connection terminals 43 firstly is formed by performing filmformation in a predetermined shape by Cu plating to a positioncorresponding to the protruding portion 43 a of the base material 42,and thereafter, masking the end surface and forming Cu plating on thefirst main surface and the second main surface including the Cuprotruding portion. Then, the mask of the end surface is removed, andNi/Au are plated onto the first main surface, the end surface and thesecond main surface to thereby enable formation of the connectionterminal 43.

The substrate includes a reinforcing terminal 43 c on the second mainsurface corresponding to the mounting region of the light emittingelement 5 a.

The second main surface of the substrate is covered by an insulatingfilm 8 from a portion in proximity to the central portion of thesubstrate of the pair of connection terminal 43 and across the basematerial 42 and the reinforcing terminal 43 c.

As illustrated in FIG. 8E, a portion of the connection terminal 43 isformed with a small width on the first main surface of the substrate.Furthermore, as illustrated in FIG. 8G, a portion of the connectionterminal 43 is also formed with a small width on the second mainsurface.

As illustrated in FIG. 8C, the light emitting element 5 a is formed by apair of electrodes and a semiconductor laminated body, and then thesubstrate for growth of the semiconductor layer is removed. The removalof the element substrate for growth of the semiconductor layer, forexample, can be performed by use of a laser lift off method or the likeby mounting a light emitting element 5 that has the element substratefor growth of the semiconductor layer on a pair of connection terminals,disposing the light reflecting member 7 and then irradiating laser light(for example, a KrF excimer laser) onto the semiconductor layer from thesapphire substrate side to thereby produce a decomposition reaction onthe interface between the semiconductor layer and the sapphire substrateand separate the sapphire substrate from the semiconductor layer. Atthat time, the semiconductor layer for the light emitting element iscovered by the light reflecting member 7, and furthermore the lightemitting element can be accurately fixed by covering both the moltenmember 6 and the protruding portion 43 a of the connection terminal 43.Therefore, the stress produced by illumination of laser light can bereduced, and it is possible to efficiently remove the sapphire elementsubstrate from the semiconductor layer.

The pair of electrodes on the light emitting element 5 a is bonded bythe molten material 6 that is configured from an Au—Sn eutectic solderand the protruding portion 43 a of the connection terminal 43. The firstmain surface of the light emitting element 5 a includes a ceramic platethat contains a fluorescent material and is configured by a lighttransmissive member 10 a fixed by light transmissive silicon resinadhesive. The end surface of the light transmissive member 10 a iscovered by the light reflecting member 7.

An insulating member 9 is disposed on the connection terminal 43 betweenthe protruding portion 43 a and the outer connection portion. Theinsulating member 9 is formed substantially in a rectangularparallelepiped configuration with a length in a longitudinal directionof 0.5 mm, a width in the short direction of 0.4 mm and a thickness of0.02 mm. The insulating member 9 is exposed by 0.3 mm in a longitudinaldirection from the end surface of the light reflecting member 7. Theinsulating member 9 covers the small width portion and the periphery ofthe connection terminal 3.

The edge portion facing the longitudinal direction of the lightreflecting member 7 is disposed on the insulating member 9, and the edgeportion along the longitudinal direction of the light reflecting member7 coincides with the edge portion along the longitudinal direction ofthe insulating member 9. Furthermore, the edge portion along thelongitudinal direction of the insulating member 9 coincides with theedge portion along the longitudinal direction of the substrate, and theend surface along the longitudinal direction of the insulating member 9is formed to be coplanar with the end surface along the longitudinaldirection of the substrate. The insulating member 9 is formed from whitesilicon resin containing titanium dioxide.

In case where disposing the insulating member in this manner, asdescribed below, if the light emitting device is mounted on the mountingboard in a side-view configuration, it is possible to avoid penetrationof solder along the surface of the connection terminal and thereby avoida reduction in the reliability of the light emitting device.Furthermore, when connecting the light emitting element to theconnection terminal by the molten material, it is possible to preventleakage of the molten material from the protruding portion and theadjacent area thereto onto the outer connection portion.

Features other than those described above are similar to the firstembodiment, and therefore the same effect as the first embodiment can beimparted.

Fifth Embodiment

As illustrated in FIG. 9A to FIG. 9E, the light emitting device 50 ofthe present embodiment is such that a translucent glass plate and afluorescent material layer 10 c coated by spraying onto the surface ofthe plate are disposed as a light transmissive member 10 b on the lightemitting element 5.

Features other than those described above are similar to the fourthembodiment, and therefore the same effect as the fourth embodiment canbe imparted.

Sixth Embodiment

As illustrated in FIG. 10, the light emitting device of the presentembodiment has similar configuration to the light emitting deviceaccording to the fourth and the fifth embodiments with the exceptionthat the planar shape of the protruding portions 53 a in the connectionterminal 53 is formed in the shape of a letter X. Therefore, the sameeffect as the first, fourth and fifth embodiments can be imparted. Inaddition, the formation of the shape of the protruding portion in theshape of a letter X facilitates storage of the molten material in arecessed position when viewed in plan and enables further ensure anaccurate and strong connection with the light emitting element.

Seventh Embodiment

As illustrated in FIG. 11, the light emitting device 60 of the presentembodiment includes through holes 62 a in proximity to both ends in thelongitudinal direction of the base material 62, and a pair of connectionterminal 63 extends from the upper surface through the through hole 62 ato the lower surface of the substrate. The light emitting device 60 hassimilar configuration to the light emitting device according to thefirst and the fourth embodiments with the exception that the end surfaceis not covered, and therefore the same effect as the first and thefourth embodiments can be imparted.

Eighth Embodiment

As illustrated in FIG. 12A to FIG. 12G, the light emitting device 70 ofthe present embodiment includes a substrate including a base material72, a pair of connection terminal 73 formed on the surface of the basematerial 72, one light emitting element 5, and a light reflecting member7. The light emitting element 5 is connected by the molten material &tothe two protruding portions 73 a provided on the pair of connectionterminal 73. Furthermore, as illustrated in FIG. 12E, an insulating film78 is provided between the pair of connection terminals 78 on the rearsurface of the substrate. Furthermore, a light transmissive member 10 dis provided that includes a fluorescent material and which covers theupper surface of the sealing member 7 and the upper surface of the lightemitting element 5.

The light emitting device 70 has similar configuration to the lightemitting device according to the first embodiment with the exceptionthat there is a difference the shape of the pattern of the pair ofconnection terminal 73 disposed on the base material 72 and the size ofthe protruding portions 73 a formed on the surface of the connectionterminals 73, and that the four end surfaces of the light transmissivemember 10 d coincide with the four end surfaces of the light reflectingmember 7, and therefore the same effect as the first embodiment can beimparted.

The light emitting element 5 is an LED chip that capable to emit bluelight (central emission wavelength of 455 nm) in a rectangularparallelepiped configuration with a length in a longitudinal directionof 0.8 mm, a width in the short direction of 0.3 mm and a thickness of0.1 mm.

The substrate 4 is formed approximately in a rectangular parallelepipedconfiguration with a length in a longitudinal direction of 2.2 mm, awidth in the short dimension direction of 0. 4 mm and a thickness of 0.3mm. The light reflecting member 7 is formed approximately in arectangular parallelepiped configuration with a length in a longitudinaldirection of 1.2 mm, a width in the short direction of 0.4 mm and athickness of 0.3 mm.

As illustrated in FIG. 12G, the light emitting device 70 can bemanufactured by similar manner to the first embodiment by use of anaggregate substrate having an aggregate connection terminal 73 c on thebase material 72 c. The aggregate substrate is configured from aplurality of connected the substrates of each light emitting device asillustrated in FIG. 12D and FIG. 12E after the singulating step.

Ninth Embodiment

As illustrated in FIG. 13A to FIG. 13G, the light emitting device 80 ofthe present embodiment includes a substrate including a base material82, connection terminals 83 and a second connection terminal 83 c formedon the surface of the base material 82, two light emitting elements 5,and a light reflecting member 7.

The light emitting device 80 has similar configuration to the lightemitting device according to the first embodiment with the exceptionthat there is a difference in the number of light emitting elements 5,the shape of the pattern of the connection terminals 83 disposed on thebase material 82, the size of the protruding portions 83 a formed on thesurface of the connection terminals 83, and that the four end surfacesof the light transmissive member 10 d coincide with the four endsurfaces of the light reflecting member 7, and therefore the same effectas the first embodiment can be imparted.

The two light emitting elements 5 are in a rectangular parallelepipedconfiguration with a length in a longitudinal direction of 1.1 mm, awidth in the short direction of 0.2 mm and a thickness of 0.2 mm, andmounted at intervals of 0.4 mm in a longitudinal direction of thesubstrate.

The substrate 4 is formed approximately in a rectangular parallelepipedconfiguration with a length in a longitudinal direction of 3.5 mm, awidth in the short dimension direction of 0. 4 mm and a thickness of0.15 mm. The light reflecting member 7 is formed approximately in arectangular parallelepiped configuration with a length in a longitudinaldirection of 3.0 mm, a width in the short direction of 0.4 mm and athickness of 0.2 mm at a center on the first main surface of thesubstrate.

The base material 82 includes through holes 82 d between the two lightemitting elements 5 and embeds the through holes 82 d so that the secondconnection terminal 83 e extends to the rear surface of the substrate.In this configuration, the second connection terminal 83 e is providedbetween two light emitting elements 5 on the rear surface of thesubstrate. More specifically, it is located between the two insulatingfilms 84 b provided respectively directly below the two light emittingelements on the rear surface of the substrate. The two insulating films84 b are placed in contact with the base material 82, and are providedseparately from the respective connection terminal 83 and secondconnection terminal 83 e. The second connection terminal 83 e is exposedand not covered by the insulating film on the rear surface of thesubstrate, and when the light emitting device is mounted, it functionsas a thermal radiation terminal by connection with a bonding materialsuch as solder, or the like.

A light transmissive member 10 d that contains a fluorescent material isprovided to cover the upper surface of the sealing member 7 and theupper surface of the two light emitting elements 5.

As illustrated in FIG. 13G, the light emitting device 80 can bemanufactured by similar manner to the first embodiment by use of anaggregate substrate having an aggregate connection terminal 83 c on thebase material 82 c. The aggregate substrate is configured from aplurality of connected substrates of each light emitting device asillustrated in FIG. 13D and FIG. 13E after the singulating step.

Tenth Embodiment

As illustrated in FIG. 14 to FIG. 16, the light emitting device 1A ofthe present embodiment has a substrate 4 that has a pair of connectionterminal 3, a light emitting element 5, and a light reflective member 7.

The substrate 4 has a pair of connection terminals 3 formed bylaminating Cu/Ni/Au from the base material 2 side onto the surface (theupper surface 2 a that is the first main surface, and end surface 2 bthat extends in the direction of the short dimension, and the lowersurface 2 c that is the second main surface) of the rectangularparallelepiped base material 2 that is formed by a glass epoxy resin.The substrate 4 is served as a wiring base and has a length in alongitudinal direction of 2.2 mm, a width in the short dimensiondirection of 0.4 mm and a thickness of 0.3 mm.

The pair of connection terminals 3 includes an element connectionportion 3 c in a mutually adjacent configuration on a central portion ofthe upper surface 2 a side of the base material 2. The pair ofconnection terminals 3 extends respectively from the element connectionportion 3 c in the longitudinal direction, from the upper surface 2 a ofthe base material 2 through respective end surface 2 b to the lowersurface 2 c of the substrate. The outer connection portions 3 b of theconnection terminals 3 are positioned where extend from the elementconnection portion 3 c and to the lower surface 2 c of the base material2 (position in the shape of a letter U when viewed in cross section)(reference is made to FIG. 15). The edge portion along the longitudinaldirection of each connection terminal 3 coincides with the edge portionalong the longitudinal direction of the substrate 4, and the end surfacealong the longitudinal direction of each connection terminal 3 is formedcoplanar with the end surface along the longitudinal direction of thesubstrate 4.

Each connection terminals 3 includes a small width portion between theelement connection portion 3 c and the outer connection portions 3 b,respectively (reference is made to FIG. 16). A portion of the outerconnection portions 3 b on the second main surface of the substrate 4includes a small width portion.

The light emitting element is mounted on the connection portion 3 c ofthe substrate 4 by flip-chip manner.

The light emitting element 5 is formed of a laminated body (asemiconductor laminate) of a nitride semiconductor on a sapphiresubstrate, and includes a pair of positive/negative electrodes on thesurface that is opposite to the sapphire substrate of the laminatedbody. The pair of positive/negative electrodes of the light emittingelement 5 is bonded by bonding agents 6 that is Au—Sn eutectic solder tothe connection portion 3 c of the pair of connection terminals 3 on thesubstrate 4. The light emitting element 5 is an LED chip that capable toemit blue light (central emission wavelength of 455 nm) in a rectangularparallelepiped configuration with a length in a longitudinal directionof 0.8 mm, a width in the short direction of 0.3 mm and a thickness of0.1 mm.

The sealing member 7 is formed approximately in a rectangularparallelepiped configuration with a length in a longitudinal directionof 1.2 mm, a width in the short direction of 0.4 mm and a thickness of0.3 mm. That is to say, the edge portion along the longitudinaldirection of the sealing member 7 respectively coincides with the edgeportion along the longitudinal direction of the substrate 4. The sealingmember 7 is provided on the first main surface of the substrate 4 incontact with the light emitting element 5 and to cover the entireperiphery of the end surface of the light emitting element 5.Furthermore, the sealing member 7 is also provided on the surface facingthe substrate 4 of the light emitting element 5, and between the moltenmaterials 6.

In this manner, light from the light emitting element 5 to the uppersurface of the light emitting device can be efficiently extracted.

The sealing member 7 is formed by a silicon resin in which silica havingan average particle diameter of 14 microns and titanium oxide having anaverage particle diameter of 0.25 microns to 0.3 microns arerespectively composed as 2 to 2.5 wt % and 40 to 50 wt % relative to thetotal weight of the sealing member 7.

A portion of the small width portion of each connection terminal 3 andthe outer connection portions are exposed from the sealing member 7 onboth sides of the sealing member 7 on the substrate 4.

The edge portion along the longitudinal direction of the sealing member7 coincides with the edge portion along the longitudinal direction ofthe substrate 4, and the end surface along the longitudinal direction ofthe sealing member 7 is formed coplanar with the end surface along thelongitudinal direction of the substrate 4.

Insulating members 9 are disposed on the connection terminal 3 andbetween the element connection portion 3 c and the outer connectionportion. Each of the insulating members 9 are formed approximately in arectangular parallelepiped configuration with a length in a longitudinaldirection of 0.5 mm, a width in the short direction of 0.4 mm and athickness of 0.02 mm. The insulating member 9s are exposed by 0.3 mm ina longitudinal direction from the end surfaces of the sealing member 7.The insulating members 9 cover the small width portion and the peripheryof the pair of the connection terminal 3 respectively.

The edge portion facing the longitudinal direction of the sealing member7 is disposed on the insulating members 9, and the edge portion alongthe longitudinal direction of the sealing member 7 coincides with theedge portion along the longitudinal direction of the insulating members9. Furthermore, the edge portion along the longitudinal direction of theinsulating members 9 coincides with the edge portion along thelongitudinal direction of the substrate, and the end surface along thelongitudinal direction of the insulating member 9 is formed to becoplanar with the end surface along the longitudinal direction of thesubstrate.

The insulating member 9s are formed from white silicon resin containingtitanium dioxide.

A light transmissive member 10 configured as a sheet of silicon resin(thickness 0.1 mm) that includes a YAG:Ce fluorescent material isdisposed on the light emitting element 5, that is to say, on theopposite surface of the surface in which the pair of positive andnegative electrodes formed.

The end surfaces of the light transmissive member 10 are covered by thesealing member 7. The upper surface of the light transmissive member 10and the upper surface of the sealing member 7 are formed in a coplanarconfiguration.

As illustrated in FIG. 17, the pair of end surfaces along thelongitudinal direction of the substrate 4 and the pair of end surfacesalong the longitudinal direction of the light reflecting member 7 of thelight emitting device 1A are disposed respectively in a coplanarconfiguration. The light emitting device 1A is mounted in a side-viewmanner on the mounting board 51 that has a surface wiring pattern 52.One of the end surfaces in the coplanar configuration is served as amounting surface of the light emitting device 1A. The mounting isconfigured so that the pair of outer connection portions 3 b of thelight emitting device 1A is respectively disposed on the wiring pattern52 corresponding to the positive and negative electrodes of the mountingboard 51, and is connected by solders 54. The solder 54 is connectedwith the small connection terminal 3 at the end surface and the secondmain surface in addition to the first main surface of the substrate 4 onthe outer connection portion 3 b that is curved in the shape of theletter U. In this manner, a solder fillet can be formed on the sidesurfaces of the light emitting device 1A and thereby enhances themounting stability and thermal radiation performance of the lightemitting device 1A.

The disposition of a small width portion between the element connectionportion 3 c and the outer connection portion 3 b in the connectionterminals 3 can suppress penetration under the sealing member 7 ofsolder or the like and flux or the like contained therein that areconnected with the outer connection portion 3 b.

Both one of the end surface along the longitudinal direction of thesubstrate 4 and one of the end surface along the longitudinal directionof the sealing member 7 are in contact with the surface of the mountingboard 51.

The sealing member 7 itself is provided with an extremely thin wallconfiguration on the periphery of the light emitting element 5, andtherefore it is possible to sufficiently downsize the light emittingdevice 1A. Furthermore, the formation of the sealing member 7 with thelight reflecting or light blocking material enables extraction of light,which emits to lateral direction of the light emitting element toreflect to upward of the light emitting device by the light reflectingmember 7. Therefore, the use efficiency of the light can be enhanced.

As illustrated in FIG. 18A and FIG. 18B, the light emitting device 1Acan manufactured by use of an aggregate substrate 14 that has anaggregate connection terminal 13 on the base material 12. The aggregatesubstrate 14 is configured by connection of a plurality of units thatform the substrate of each light emitting device 1A after thesingulating process.

The aggregate substrate 14 includes slits 15 from the upper surface tothe rear surface of the base material 12. The aggregate connectionterminal 13 is provided in connection from the upper surface to thelower surface of the base material 12 of the aggregate substrate 14through the inner wall of the slits 15.

Although FIG. 18A shows the aggregate substrate 14 which forms eighteenlight emitting devices, the aggregate substrate 14 can be configured toform more numerous (several hundred to several thousand) light emittingdevice 1A when manufacture efficiency is considered.

The insulating members 19 are integrally-formed on the aggregatesubstrate 14 which includes a plurality of the substrate. Then, aplurality of light emitting element 5 are connected on the aggregatesubstrate 14 and the light transmissive members 10, that havesubstantially the same shape as the light emitting element 5 in a planview, are adhered onto each of the light emitting element 5. A pluralityof sealing members 17 is formed in a single operation by use ofcompressive molding to cover the end surface of the light transmissivemember and the light emitting element. Then the aggregate substrate 14and the sealing members 17 are cut in a single direction along thepredetermined dividing lines L which intersect with the slits 15 atsubstantially right angles. In this manner, division along the directionof extension of the slits is enabled to obtain light emitting devicesseparated into units in comparatively few processing steps.

A dicer, a laser, or the like can be used in the cutting process.

Eleventh Embodiment

As illustrated in FIGS. 19A and 19B, the light emitting device 20Aaccording to this embodiment includes a substrate 24 that has connectionterminals 23, a plurality of light emitting elements 5, and a sealingmember 27.

Each of the connection terminal 23 are disposed on the base material 22so as to extend to the upper surface, the end surface and the lowersurface on both sides in the longitudinal direction of the base material22. Furthermore, further terminals 25 which can connect a plurality oflight emitting elements 5 for example in series and is disposed on theupper surface of the base material 22.

A plurality of light emitting elements 5 is disposed by alignment into aline. The arrangement of the light emitting elements is also possibleinto a matrix configuration in addition to a linear configuration.

The sealing member 27 integrally seals the plurality of light emittingelement 5. The end surfaces along the longitudinal direction of thesealing member 27 are formed coplanar with the end surfaces along thelongitudinal direction of the substrate 24. The edge portion facing theshort direction of the sealing member 27 is disposed on the inner sideof the substrate 24.

The insulating members 29 are disposed such that each edge portion in ashort direction of the sealing member 27 is positioned on the insulatingmember 29 respectively.

It is preferred that a recessed portion or through hole is formed in thesubstrate 24 between the light emitting elements 5, and a portion of thesealing member 27 is filled into the recessed portion or the throughhole to thereby seal the sealing member 27 to the substrate 24. In thismanner, the adhesion between the sealing member 27 and the substrate 24can be enhanced, and it is possible to prevent peeling of the sealingmember 27 from the substrate 24.

Features other than those described above are similar to the tenthembodiment, and therefore the same effect as the tenth embodiment can beimparted. Furthermore, the light emitting device of the presentembodiment can be used as a linear or matrix type side-view lightemitting device. Therefore, the light emitting device enhances mountingaccuracy in comparison to mounting individual side-view light emittingdevices on a mounting board respectively. Furthermore, alignmentcharacteristics with the light guide plate are enhanced in case wherefunctioning for example as a backlight light source.

Twelfth Embodiment

As illustrated in FIG. 20, the light emitting device 30A according tothe present embodiment arranges a plurality of light emitting deviceaccording to the tenth embodiment are connected each other into thedirection of a row or a matrix in a configuration that the lightemitting devices sharing the adjacent connection terminals 33, and inparticular the outer connection portion 33 b. Through holes are providedin the base material 32 between adjacent light emitting elements 5, andthe connection terminals 33 are drawn towards the lower surface side ofthe substrate 34 through the through holes.

Features other than those described above are similar to the tenthembodiment. Therefore, the same effect as the first embodiment can beimparted, and the same effect as the second embodiment can be alsoimparted.

The light emitting device according to the present invention can be usedfor back light sources for liquid crystal displays; various kinds oflighting apparatus; large-size displays; various kinds of displays foradvertising, direction information guide and the like; image scannerssuch as digital video camera, facsimile, coping machine, scanner;projector apparatus ant the like.

As illustrated above, embodiments are described to give a concrete fontto technical ideas of a light emitting device according to the presentinvention, the present invention is not limited to the describedembodiments of the present invention. Also, obviously, numerousmodifications and variations of the present invention are possible inlight of the above teachings, which are within the scope and spirit ofthe invention, and such other modifications and variations are intendedto be covered by the following claims.

What is claimed is:
 1. A light emitting device comprising: a substrateincluding a base material having a rectangular planar shape, aconnection terminal disposed on a first main surface of the basematerial, and an outer connection portion disposed on a second mainsurface of the base material opposite to the first main surface, theconnection terminal including a protruding portion, and the connectionterminal being connected to the outer connection portion via a throughhole defined in the base material; a light emitting element connected tothe connection terminal on the first main surface of the base materialvia a molten bonding material; and a light reflecting member coveringthe light emitting element.
 2. The light emitting device according toclaim 1, wherein the through hole is disposed at a position near an edgein a longitudinal direction of the base material.
 3. The light emittingdevice according to claim 1, wherein the molten bonding material coversa side surface of the protruding portion of the connection terminal. 4.The light emitting device according to claim 1, further comprising theprotruding portion projects from a first main surface of the connectionterminal, and the protruding portion is spaced apart from an edge of thefirst main surface of the connection terminal.
 5. The light emittingdevice according to claim 1, wherein the light reflecting member fills aspace between the base material and the light emitting element.
 6. Thelight emitting device according to claim 1, wherein a first main surfaceof the light emitting element is flush with or positioned lower than afirst main surface of the light reflecting member.
 7. The light emittingdevice according to claim 1, further comprising a light transmissivemember disposed over the light emitting element, wherein the lightreflecting member covers an end surface of the light emitting elementand an end surface of the light transmissive member.
 8. The lightemitting device according to claim 1, further comprising an additionallight emitting element, wherein the substrate further includes a pair ofinsulating members disposed on the second main surface of the basematerial respectively in regions corresponding to the light emittingelement and the additional light emitting element, the outer connectionportion is disposed between the insulating members.
 9. The lightemitting device according to claim 2, wherein the molten bondingmaterial covers a side surface of the protruding portion of theconnection terminal.
 10. The light emitting device according to claim 2,further comprising the protruding portion projects from a first mainsurface of the connection terminal, and the protruding portion is spacedapart from an edge of the first main surface of the connection terminal.11. The light emitting device according to claim 2, wherein the lightreflecting member fills a space between the base material and the lightemitting element.
 12. The light emitting device according to claim 2,wherein a first main surface of the light emitting element is flush withor positioned lower than a first main surface of the light reflectingmember.
 13. The light emitting device according to claim 2, furthercomprising a light transmissive member disposed over the light emittingelement, wherein the light reflecting member covers an end surface ofthe light emitting element and an end surface of the light transmissivemember.